When a defensive back says, "we'll win," it just doesn't have the same ring as a Joe Namath guranteeing a Super Bowl victory as a despised underdog.

But when safety Paul Krause of the Minnesota Vikings flies in the faces of the Dallas Cowboys and coolly forecasts an upset in Sunday's playoff game, he at least can claim an analogy to Namath's onetime New York Jets: the Vikings are despised, too, Krause says.

"Nobody wanted us to beat the Rams," Krause said, "the league or the television people."

Reminded that all Americans are a cult of rooters for the underdog, Krause said, "No, they are tired of seeing us in the big games, with all those losses in the Super Bowl.

"There was that old . . . about how old the Vikings are, and all that stuff . . . about how the Rams blew us off the field in that Monday night game. Yet, the Rams have never beaten us in a big game.

"We just took it to them on Monday . . . on offense and defense."

Did coach Bud Grant perhaps make a few remarks before the game about the Vikings having everybody against them?

"He would never do that. He didn't have to. We knew the Rams thought they would not have much of a problem with us."

Yes, but how do the Vikings hope to beat the Cowboys whom the Vikings saw demolish the Chicago Bears on television?

"That's just what everybody was saying about the Rams before we beat them. The Cowboys can't beat us merely by throwing their hats on the field. They were good looking against the Bears. The Cowboys are a very fine Club, but we'll show up."

Krause is 35 years old, in his 14th season and is starting his second head of hair, courtesy of some artificial stuff woven in with his leftovers by the Apollo Celebrity Hair Center, a nationwide chain in which he has an investment, but he says he going to play until he is 40.

One reason is that he wants to break the National Football League record for interceptions held by the late Emlen Tunnell, former New York Giants and Green Bay Packers defensive back, at 79.

Krause finally got his third interception of the season for No. 79 against the Rams, but learned that it didn't count for the record, because it came in a playoff game.

"It should count," Krause said, "but I am going to play again; there is more football left in me. I feel good. I had a good training camp; I could last five years."

It was mentioned that he not only beat out Bill Bradley, who came from the Philadelphia Eagles, but did so well that Bradley was dropped.

"Yeah, and he came to Minnesota with a two-year no-out contract (which means the Vikings are still playing him). They had a big press conference, as if he was an All-Pro. It was very satisfying to me.

"There is no doubt I can still play. I had a good year. I made a lot of tackles (a self-conscious issue with him because he supposedly was traded by Otto Graham to the Vikings because he was not a satisfactory tackler).

"I had only two interceptions during the regular season because teams did not have to throw on us. They could run on us. That's no secret, Walter Payton ran for 275 yards against us. I would have 81 interceptions, lifetime, if they counted the three in playoff and championship games."

He was not a bad acquistion for the Vikings, who gave up tight end-line-backer Marlin McKeever to the Red-skins for him. McKeever has been out of the NFL since 1972.